 The gun uses an automatic loading system where 66 127mm rounds of various kinds can be stored ready-to-fire in three loader drums (each holding 22 rounds).The barrel is water-cooled.Currently the gun is still in use by navies around the world but it is slowly being replaced by the Otobreda 127/64 for new vessels, such as the German Navy's F125-class frigate and Italian Navy's FREMM.